Overhead door



c. E. WHITE OVERHEAD DOOR Filed March 27, 1930 2 sheets-sheet 1 c. E. WHITE 2,033,913

OVERHEAD DOOR l Patented Mar. 10, 1936 VERHEAD DOOR Chantilla E. White, Indianapolis, Ind., assignor of one-half to .lohn A. White, Indianapolis, Ind.

Application March 27, 1930, Serial No. 439,342

15 Claims.

My invention relates to overhead doors. Such doors, frequently used for garages, are opened by raising and closed by lowering, and slide on tracks by which they are guided into a substantially vertical position when lowered or closed and to a position more or less closely approaching the horizontal when raised or opened.

It is the. object of my invention to simplify the mounting and operation of such doors, and to remove certain difficulties and dangers which have heretofore attended their use.

In such overhead doors, it is desirable and often necessary that they be counterbalanced, so that less effort may be required to raise the doors.

The effective door-weight to be counterbalanced, however, varies with the position. of the door, from a maximum when the door is lowered or closed to a minimum when the door is raised or opened. This variable counterbalancing has been obtained heretofore in various ways. One important way has been by a counterbalancing spring which carries the weight of the door and is increasingly stressed and so caused to exert an increasing spring-force as the door is lowered, to take care of the greater eiective weight of the door as it moves to the vertical position. If the spring breaks in such an arrangement, the counterbalancing of the door is destroyed, and the full weight of the door becomes effective; thus creating a tendency for the door to freely drop to closed position, sometimes with disastrous effects on anything or anything or any person that may be in the path of the descending door.

By my present invention I avoid the danger of accidents such as these.

To this end, speaking rather generally, I counterbalance the weight of the door by a counter-weight or counter-weights; and to get the variable counterbalancing which is desirable, I provide a spring which opposes the descent of the counter-weight, with a variable spring-force which increases as the counter-weight descends and which therefore increases as the door rises instead of as the door descends. With this arrangement, any breaking of' the spring causes the full weight of the counter-weight to become eiiective, instead of causing the full weight of the door to become effective; so that a breakage of the spring results in an increased tendency for the door to move upward or to open position, instead of the dangerous tendency heretofore present for the door to move downward to its closed position.

55 In other words, with the present invention,

(Cl. 2li-20) breakage of the spring causes the door to move upward, and not downward.

The accompanying drawings illustrate my invention: Fig. l is a side elevation of an overhead door and its mounting, in accordance with 5 my invention, with the door substantially closed and with some parts in section on the line I--ll of Fig. 2; Fig. 2 is a section on the line 2-2 of Fig. 1; Fig. 3 is a View generally similar to Fig. 1 but of a slightly modied structure, and with the l0 sectioned parts in section substantially on the line 3 3 of Fig. 10; Fig. 4 is an enlarged fragmental detail of part of Fig. 3, but with the door not quite closed; Fig. 5 is a detail of a modiiied adjusting device for the upper end of the counterl5 balancing spring of Fig. 1; Fig. 6 is a semi-diagrammatic View on a smaller scale to show the use of a pair of compression springs instead of the tension spring of previous views; Fig. '7 is a semi-diagrammatic fragmental View, generally 20 similar to Fig. 1 but on a smaller scale, showing the counter-weight and its opposing spring located at the rear of the garage or other point remote from the door; Fig. 8 is a semi-diagrammatic elevation of the door, with a single spring- 25 opposed counter-weight connected to both sides of the door; Fig. 9 is a view similar to Fig. 8 but showing separate spring-opposed counter-weights for the two sides ci the door; and Fig. 10 is a section substantially on the line lilifi of Fig. 3. 30

The overhead door i@ usually comprises a plurality of sections, of any -desired number but for convenience here shown as four in number. The number of sections may vary from one section, comprising the whole door, to a considerable number of sections, similar to the sections of the flexible top of a roel-top desk. The door sections are hinged together by hinges l i, having pivot pins i2.

The door sections are guided by rollers i3, suitably mounted on the edges of the doors. As shown, some of these rollers are mounted on eX- tensions of the pivot pins i2 of the hinges Il.

This provides rollers i3 at or near each joint between door sections. In addition to the rollers thus provided at or near the hinges, there are desirably similar guide rollers i3 at or near the bottom of the lowermost door section and at or near the top of the topmost door section; and these two rollers are mounted on similar pins l2 50 carried by plates lia attached to the door sections and corresponding to hinge-halves but provided here merely for mounting the pins. The pins I2 are slightly cranked, as is perhaps best shown in Fig. 4, so that the axes of the guide 5,5

rollers I3 hang down slightly below the axes of the hinges II and hinge halves IIa.

The guide rollers I3 travel in guideways I4, which are located at either side of the doorway which the door is to close and are vertical along the sides of such doorway but are bent backward away from the doorway into a position more or less closely approaching the horizontal after they have passed upward beyond the top of the door opening.

The door opening has the usual door jambs I5 and lintel I6. It is desirable that the door IU should bear against these door jambs and this lintel -When the door is closed. To this end, the side edges of some of the door sections are provided with pins I1, projecting successively greater distances outward toward the top of the door than toward the bottom, which co-operate with upwardly projecting inclined fingers carried by the door jambs I5 at each side of the door and set successively farther from the door edge toward the top of the doorway, as is shown in Figs. 3 and 10. In consequence, when the door is lowered, each projecting pin I1 passes the finger or fingers I8 which are higher than the one it is to engage, but each engages its own particular finger I8 and coacts therewith by an inclinedplane action to force the door forward tight against the door jambs and lintel. As shown in both the modiiication of Figs. 1 and 2 and the modification of Figs. 3, 4, and 10, there are two such pins I1 and two fingers I8 on each side of the door, in connection with the upper two sections thereof; but there may be any desired number.

In the form shown in Figs. 3, 4, and 10, the fingers I8 project from the jamb the full thickness of the door, in order to permit a substantial backward movement of the door on opening and still ensure the engagement of such fingers with the pins I1 on closing even though such pins are placed a substantial distance from the front side of the door. However, it is possible to save lateral space, especially when the counter-weights are placed at the sides of the door, by making the lingers I8 somewhat shorter and thus obtaining a more compact cross-sectional arrangement of the track IU and arm 26, as is shown in Fig. 2.

To force the bottom door section forward when the door is lowered, a slanting plate I9 is provided at the b-ottom of each guideway I4, to co-operate with the lowermost pin I2 or the plate IIa which carries it, as is clear from Fig. 3.

The inclined plates I9 and the inclined ngers I8 come to action simultaneously as the door drops into its lowermost position, to force the door forward against the door jambs and lintel; and the cranked pins I2 permit this forward movement of the door by the turning of the crank-arms of such pins to an oblique position, such as is indicated in Fig. 3. When the door is raised from its lowermost position, it swings away from the door jamb and lintel by a reverse swinging of such crank-arms; so that during the main part of its movement the door sections are out of contact with the door jambs and lintel.

A rope, chain, or cable 25 is connected to the door at each side thereof, usually to the lowerrnost door section at or near the bottom thereof. Such connection may be by an arm 26 extending from the back side of the door to a point opposite the side of the door in position not to interfere with the fingers I8 as the door is raised. Each rope, chain, or cable (hereinafter called aoaaso simply a cable) passes upward at the side of th lowered door to a fixed pulley 21, and thereafter to a counter-weight 28. The. two cables 25 may pass to separate counter-weights 28, as indicated in Fig. 9, or to a single counter-weight 28 as indicated in Fig. 8; and the counter-weight 28 may be located near the doors I8 when the latter are in Vertical position, as on one or both sides thereof as is shown in Figs. 8 and 9 respectively, or at some remote place, such as the rear of the garage, as is indicated in Fig. 7. To this end, there may be any necessary number of intermediate pulleys 29 in the course of the cable 25 between the pulley 21 and the counter-weight 28.

Preferably, in order to lessen the length of vertical movement of the counter-weight 28, the cable 25 is not positively attached thereto, but passes around a movable pulley 38 mounted on said counter-weight, and thence upward to a fixed anchorage point 3|; as in an adjustable eyebolt 3I, which may be an adjustable eye-bolt as indicated in Fig. 1. By having the eye-bolt adjustable, it is possible by tightening it to compensate for any stretch that may occur in the associated cable 25.

Desirably the counter-weights 28 slide in Vertical guideways 33, shown as T-irons whose stem anges project into slots extending along opposite sides of the counter-weights, as is clear from Fig. 2. However, other guides may be provided, such as a pair of vertical posts 34 which extend through holes in the counter-weight, as is shown in Fig. 6.

Each counter-weight 28 is associated with one or more springs which is stressed as the counterweight descends. Such springs may be tension springs 35, as illustrated in Figs. 1, 2, 5, '1, 8, and 9, with the lower end of each spring suitably attached to its counter-weight in any suitable manner; or compression springs 36, on which the counter-weights 28 rests, as in Fig. 6. If the springs are the tension springs 35, their lower ends may be attached to the counter-weights 28 by a cross-pin 31, as is illustrated in Figs. 1 and 2; -or they may be attached to the yokes 38 of the movable pulleys 38 in the manner illustrated in Figs. 1, 8, and 9. The attachment shown in Figs. 1 and 2 permits the springs 31 to be largely within the counter-weights, which are hollow for that purpose; in which case the movable pulleys 30 for those counter-weights may be located either at or near the bottom thereof in the manner shown in Fig. l. This construction is especially advantageous where height is restricted, for it permits the spring and the weight to overlap; and also where space for the weights is restricted, for it permits the use of a long slender weight without increasing the height of the apparatus as a whole.

If the springs are tension springs 35, their upper ends may be attached to some fixed point, desirably adjustable, such as an adjustable eyebolt 39, as in Figs. l, 8, and 9, or to a cable 40 extending over a sheave on an adjustable ratchet GI as is shown in Fig. 5, or even to the yoke of one of the fixed pulleys such as the pulley 29 in Fig. '7. If the springs are compression springs, they may conveniently surround the posts 34, and rest on adjustable abutments 42, as is shown in Fig. 6.

. In the operation of my invention, in any of the examples shown, the counter-weight or counter-weights 28 are raised when the door I0 is lowered to its vertical or closed position. In this condition the springs 35 or 35 are wholly or relatively unstressed; for they need not be absolutely unstressed. The springs and the counter- Weights are desirab-ly so adjusted that at this time they are slightly overbalanced by the weight of the door, but only slightly so. Thus it becomes necessary to exert some lifting force to raise the door to open position, which is usually desirable. It is of course possible to have the counterbalancing such that the normal tendency is to raise the door, and force it necessary to move it downward; and if that is desired it can be obtained by adjusting the eye-bolts 39 or the ratchets lll.

In either case, when the door is raised from its substantially vertical or closed position toward its open or relatively flat position overhead, the counter-weight or counter-weights 28 descend. As the counter-weight or counter-Weights thus descend, the associated spring or springs 35 or 36 are stressed, in tension or compression as the case may be; and the stressing increases with the descent of the counter-weight or counter-weights. This stressing of the springs offsets the loss of effective weight which the door exerts on the counter-weights as it approaches its raised or overhead position. That is, as the effect of the door on the counter-weights is decreased, by

the raising of the door, the effect of the springs on the counter-weights is correspondingly increased, by the stressing of the springs.

In the same way, when the door is moved from open position to closed position, the counterweights 28 are raised; and the stressing of the springs 35 or 36 is thereby lessened. That is, in the closing of the door, the increased effect of the door on the counter-weights is offset by the decreased effect of the springs on the counter- Weights.

If the springs 35 or 36 break, or are otherwise disabled, the full effect of the counter-weights 28 comes into play; and the resultant tendency is to raise the door instead of to lower it.

I claim as my invention:

1. An overhead door structure, comprising a trackway consisting of a pair of guiding members each having relatively upright and ilat portions, a vertically openable door co-operating with and. guided by said trackway and in substantially upright position when closed and in relatively flat position when open, said door having rollers which co-operaate with said guiding members, cranked pins by which said rollers are mounted on the door to permit movement of the door transversely with respect to the plane of roller axes, means for forcing the door forward with respect to the plane of the roller axes when the door reaches its closed position, a counter-weight for the door, which counter-Weight moves downward and upward throughout substantially the whole opening and closing movements respectively of the door, and a spring opposing substantially the entire downward movement of the counter-weight.

2. An overhead door structure, comprising a trackway having relatively upright and flat portions, a vertically openable door slidable in said trackway, a counter-weight, a cable interconnecting the counter-weight and the door, and a spring opposing the tendency of the counter-weight to raise the door and acting during substantially the entire movement of the counter-weight.

3. An overhead door structure, comprising a trackway having relatively upright and flat portions, a vertically openable door slidable in said trackway, a counter-weight, said counter-weight being provided with a pulley which moves with the counter-weight, a fixed pulley, a cable extending from a fixed point around the counter-weight pulley and over the xed pulley to the door, and a spring opposing the counter-weight throughout substantially the Whole downward movement thereof 4. An overhead door structure, comprising a trackway having relatively upright and flat portions, a vertically openable door slidable in said trackway, a counter-weight, said counter-weight being provided with a pulley which moves with the counter-weight, a fixed pulley, a cable extending from an adjustable xed point around the counter-weight pulley and over the xed pulley to the door, and a spring opposing the counterweight throughout substantially the whole downward movement thereof.

5. An overhead door structure, comprising a door which is mounted to be opened by raising and to be closed by lowering, the effective weight of said door being decreased by the opening of the door, a counter-weight for the door, which counter-weight moves downward and upward throughout substantially the entire opening and closing movements respectively of the door, and a spring opposing the counter-weight throughout substantially the entire downward movement thereof.

6. An overhead door structure, comprising a trackway having relatively upright and fiat portions, a vertically openable door slidable in said trackway, a counter-Weight for the door, which counter-weight moves upward and downward throughout substantially the entire opening and closing movements respectively of the door, and a spring increasingly opposing the downward movement of the counter-weight as the door is moved from the upright portion to the flat portion of said trackway.

7. An overhead door structure, comprising a door which is mounted to be opened by raising and to be closed by lowering, the effective weight of said door being decreased by the opening of the door, a counter-weight, a cable interconnecting the counter-weight and the door, a fixed but adjustable anchorage, and a spring interconnecting said counter-weight and said xed anchorage, said spring being arranged to be increasingly stressed as the effective weight of the door decreases.

8. An overhead `door structure, comprising a door which is mounted to be opened by raising and to be closed by lowering, the effective weight of said door being decreased by the opening of the door, a counter-weight, a cable interconnecting the counter-weight and the door, a fixed anchorage, and a spring interconnecting said counter-weight and said xed anchorage, said spring being arranged to be increasingly stressed as the effective weight of the door decreases.

9. An overhead door structure, comprising a door which is mounted to be opened by raising and to be closed by lowering, a counter-weight interconnected with the door, a xed but adjustable anchorage, and a spring interconnecting said xed anchorage with one of the aforesaid movable parts to compensate for the difference in the variable effective weights of the counter-weight and of the door at different positions of the door throughout substantially the whole of the door movement.

l0. An overhead door structure, comprising a door which is mounted to be opened by raising and to be closed by lowering, a counter-weight interconnected with the door, a fixed anchorage,

and a spring interconnecting said xed anchorage with one of the aforesaid movable parts to compensate for the difference in the variable eiective weights of the counter-Weight and of the door at different positions of the door throughout substantially the Whole of the door movement.

11. An overhead door structure, comprising a trackway having relatively upright and flat portions, a vertically openable door slidable in said trackway, a spring arranged to be increasingly stressed as the weight of the door is taken by the flat portion of said trackvvay, and a Weight counter-acting the Weight of the Idoor and the stress of the spring.

12. An overhead door structure, comprising a trackway consisting of a pair of guiding members each having relatively upright and flat portions, a vertically openable door co-operating With and guided by said trackvvay and in substantially upright position when closed and in relatively fiat position When open, said door having rollers which co-operate with said guiding members, a spring arranged to be increasingly stressed as the Weight of the door is taken by the flat portion of the trackvvay, and a Weight counter-acting the Weight of the door and the stress of the spring.

13. An overhead door structure, comprising a trackway consisting of a pair of guiding members each having relatively upright and flat portions, a vertically openable door co-operating with and guided by said trackWay and in substantially upright position when closed and in relatively flat position when open, a spring arranged to be increasingly stressed as the Weight of the door is taken by the flat portion of said trackway, and a Weight counter-acting the Weight of the door and the stress of the spring.

14. An overhead door structure, comprising a trackway consisting of a pair of guiding members each having relatively upright and flat portions, a vertically openable door co-operating with and guided by said trackway and in substantially upright position When closed and in relatively flat position when open, said door consisting of a plurality of sections hinged together, and the door being provided at its lateral edges With a plurality of rollers which co-operate With said guiding members, a spring arranged to be increasingly stressed as the Weight of the door is taken by the flat portion of said trackway, and a Weight counter-acting the Weight of the door and the stress or the spring.

15. An overhead door structure, comprising a traokway having relatively upright and flat portions, a vertically openable door slidable in said trackway, an adjustably mounted spring arranged to be increasingly stressed as the Weight of the door is taken by the flat portion of said traokway, and a Weight counter-acting the Weight of the door and the stress of the spring.

CHANTILLA E. WHITE. 

